Most people see pesticides and insecticides as magic solutions that instantly eliminate insects and other common pests. Did you know, though, that it’s possible for pests to develop pesticide resistance and withstand the effects of these harsh products?

If you’ve never heard of pesticide or pest resistance, this guide will help you discover everything you need to know. It explains what resistance is, what causes it, what you can do about it, and more.

What is pesticide resistance?

Pesticides are products manufactured to control insects and other problematic organisms like weeds, bacteria, and fungi -- all of which can damage crops, especially if they aren’t addressed promptly. 

Pesticide resistance occurs when pests evolve to become less sensitive and more likely to survive pesticide exposure. They find ways to resist the effects of the pesticide and thrive in previously inhospitable environments.

When this happens, new solutions are needed to eliminate the pests and prevent them from multiplying. Otherwise, they will continue to damage crops. They will also breed and pass pesticide-resistance genes on to their offspring.

Pest resistance can occur when the same pesticide or insecticide is used repeatedly. It can also be caused by products with the same mode of action, even if they contain different ingredients.  

What causes pest resistance?

There are several types of resistance that can help pests withstand the effects of pesticides and insecticides. The following are some of the most well-known ones:

Behavioral resistance

Behavioral resistance occurs when pests begin detecting or recognizing signs of danger. As a result, they start adapting their behaviors to avoid the toxin’s effects and stay alive.

An example of behavioral resistance could be pests stopping feeding when they encounter a particular pesticide or insecticide. They may also relocate to a new area (such as moving deeper into a crop or moving to the underside of a leaf) to avoid exposure while maintaining access to their preferred food source.

Penetration resistance

Penetration resistance occurs when insects’ outer shells become stronger and more able to resist the effects of the chemicals found in pesticides and insecticides. In other words, they become impenetrable.

A more robust shell slows the absorption of the toxins. It also reduces the intensity of the toxins’ effects and increases the insects’ chances of surviving.

Metabolic resistance

As the name suggests, metabolic resistance helps insects to metabolize toxins faster. As a result, they’re able to process them more efficiently and eliminate them from their bodies before they cause harm.

Insects use internal enzymes to break down the chemicals and other ingredients in insecticides and pesticides. Pesticide-resistant insects may contain higher concentrations of these enzymes or different forms that are more effective.

Altered target-site resistance

Altered target-site resistance occurs internally. Essentially, the site in the body where the toxin binds evolves and modifies itself to reduce the insecticide or pesticide’s effects. It is one of the most common types of pesticide resistance.

What are the risks of pesticide resistance?

According to the University of Nebraska-Lincoln, pesticide resistance has severe and widespread effects (which will only worsen if the problem is dealt with). Some potential risks associated with pesticide resistance include the following:

• Increased damage to crops and lower crop yield, leading to food shortages and diminished livelihood for farmers
• Higher pest management costs
• Increased risk of environmental contamination as higher concentrations of pesticides are used
• Increased risk of human pesticide exposure (also a result of higher concentrations being used, especially on their food)

The United Nations Environmental Program has actually named pesticide resistance as the third most serious threat to global agriculture. It follows soil erosion and water pollution.

What can be done about pest resistance?

Because of the severe risks posed by pesticide resistance (and the fact that it’s becoming more common worldwide), scientists are working hard to develop solutions that slow the spread of pesticide resistance and prevent it from worsening.

The following are some of the most frequently recommended solutions:

Pest monitoring

Awareness is the first step to identifying, managing, and eventually resolving any problem -- including the issue of pesticide resistance.

Careful monitoring allows farmers and others to identify potential issues and signs of pesticide resistance. The sooner these issues have been caught, the sooner plans can be developed and implemented to prevent them from getting worse. 

Prioritizing plant health

Healthy plants and crops will be less susceptible to damage caused by insects and other pests (including those that have developed pesticide resistance).

It’s critical that, in addition to addressing pesticide-related issues, farmers and others continue to prioritize plant health. This prioritization might look like a commitment to weeding, pruning, and fertilizing, as well as the delivery of additional nutrients and regular watering.

Rotating crops

Crop rotation can also help to reduce the need to use the same pesticides every season. Crop rotation involves growing several different crops in the same area across several growing seasons.

Wisely selecting and using insecticides

Choosing and using pesticides and insecticides more carefully can also help to minimize their potential adverse effects, including pesticide resistance. Here are some specific ways that experts recommend doing this:

Alternate insecticides

Continuously using the same pesticide or insecticide creates more opportunities for pests to evolve and develop a resistance to the ingredients used in that specific product. Alternating products will help to keep plants healthy and free from pests while also creating fewer opportunities for resistance to occur.

Follow label instructions

It’s important to use pesticides and insecticides as the manufacturer recommends on the product’s label. Following instructions ensures the product isn’t overused and is used in the most effective way possible -- both of which will likely lead to better results and healthier plants.

Use the least-damaging pesticides

Many pesticides contain harsh ingredients that don’t only kill problematic insects and pests but beneficial ones as well -- including those that naturally feed on other pests.

When choosing pesticides, look for solutions that don’t harm (or at least cause the least amount of harm) natural predators. This choice helps to minimize the damage done to the area’s ecosystem and may reduce the risk of more serious environmental issues. 

Spot treat when possible

When possible, it helps to spot-treat specific areas rather than treating an entire field or plot of land with the same product. Spot-treating edges or hot spots allows you to address areas that need additional attention without blasting the entire area at once.

Some experts also recommend leaving unsprayed areas within the treated area or in nearby areas. These unsprayed areas will attract pesticide-susceptible pests that will eventually interbreed with the resistant ones. As a result, the resistance genes will be diluted throughout the population.

Time treatment properly

Correctly timing the application of pesticides ensures they produce the most significant results. Waiting until the pest is most susceptible increases the likelihood that it will be killed and won’t be able to withstand the pesticide or insecticide’s effects.

Keep detailed records 

Proper record-keeping makes it more feasible for you to keep track of critical details, like when you last used a specific product and where you used it. Your records can also help you remember what you’ve noticed when monitoring pests in the area.

The more detailed notes you have to work with, the easier it is to identify patterns and catch potential problems before they escalate.

Can pesticide resistance be reversed?

In some cases, pest resistance can also be reversed. The following are some potential solutions that can contribute to pesticide resistance reversal:

Minimize pesticide use and tank mixes

Avoid overusing pesticides, especially “tank mixes,” which involve applying multiple types of pesticides to eliminate all kinds of pests at once. Tank mixes can actually create “super pests,” creatures that are resistant to many different pesticides instead of just one.

Allow time between applications

Leaving time between pesticide and insecticide applications helps to dilute the current population naturally. As a result, they’re more likely to become susceptible to chemicals once again.

Avoid persistent pesticides

Choose pesticides that disappear quickly. Otherwise, they may create “selecting doses.” When this happens, the concentration helps to select resistant pests and turns them into the ones that pass on their genes.

Need help with pesticide-resistant pests?

It’s easy to assume that pesticide resistance is something only farmers need to worry about. In reality, though, pest resistance is a serious problem that affects everyone, including residential landowners.

Awareness and thoughtful pesticide and insecticide use are crucial in resolving this issue. Remember the guidelines discussed above to start combating pesticide resistance today.

In the meantime, if you’re worried about the potentially harmful effects certain pesticides and insecticides might have on your home or garden, Natran Green Pest Control has a solution. We only use safe, eco-friendly pest control products to treat your home without putting you, your family, or your pets at risk. 
Contact us today to learn more about our services.